folding longer expressions with pipe operator

Author: jorgsowa

src/needs-parens.mjs

@@ -90,6 +90,10 @@ function needsParens(path, options) {
             return true;
           }
 
+          if (po === "|>" && no === "|>") {
+            return false;
+          }
+
           if (pp === np && key === "right") {
             return true;
           }

src/printer.mjs

@@ -50,6 +50,7 @@ const {
   dedent,
   ifBreak,
   hardline,
+  hardlineWithoutBreakParent,
   softline,
   literalline,
   align,
@@ -114,7 +115,15 @@ function genericPrint(path, options, print) {
   }
 
   if (lineShouldEndWithSemicolon(path)) {
-    parts.push(";");
+    const isPipeChainStatement =
+      node.kind === "expressionstatement" &&
+      (node.expression.kind === "bin" && node.expression.type === "|>" ||
+        (node.expression.kind === "assign" &&
+          node.expression.right.kind === "bin" &&
+          node.expression.right.type === "|>"));
+    if (!isPipeChainStatement) {
+      parts.push(";");
+    }
   }
 
   if (fileShouldEndWithHardline(path)) {
@@ -741,6 +750,28 @@ function shouldInlineLogicalExpression(node) {
 // precedence level and the AST is structured based on precedence
 // level, things are naturally broken up correctly, i.e. `&&` is
 // broken before `+`.
+function printPipeChain(path, print, trailingSemicolon = false) {
+  const elements = [];
+
+  function collect() {
+    const { node } = path;
+    if (node.kind === "bin" && node.type === "|>") {
+      elements.push(path.call(print, "left"));
+      path.call(collect, "right");
+    } else {
+      elements.push(print());
+    }
+  }
+
+  collect();
+
+  const [first, ...rest] = elements;
+  const semicolon = trailingSemicolon
+    ? ifBreak([hardlineWithoutBreakParent, ";"], ";")
+    : "";
+  return group([first, indent(rest.flatMap((el) => [line, "|> ", el])), semicolon]);
+}
+
 function printBinaryExpression(
   path,
   print,
@@ -1524,6 +1555,7 @@ function printAssignmentRight(
 
   const canBreak =
     (pureRightNode.kind === "bin" &&
+      pureRightNode.type !== "|>" &&
       !shouldInlineLogicalExpression(pureRightNode)) ||
     (pureRightNode.kind === "retif" &&
       ((!pureRightNode.trueExpr &&
@@ -2487,6 +2519,16 @@ function printNode(path, options, print) {
       );
     }
     case "bin": {
+      if (node.type === "|>") {
+        const { parent, grandparent } = path;
+        const isStatementLevel =
+          parent.kind === "expressionstatement" ||
+          (parent.kind === "assign" &&
+            grandparent &&
+            grandparent.kind === "expressionstatement");
+        return printPipeChain(path, print, isStatementLevel);
+      }
+
       const { parent, grandparent: parentParent } = path;
       const isInsideParenthesis =
         node !== parent.body &&

tests/pipe/__snapshots__/jsfmt.spec.mjs.snap

@@ -25,14 +25,22 @@ foo($value |> transform(...), $other);
 
 $veryLongVariableName |> someVeryLongFunctionName(...) |> anotherVeryLongFunctionName(...);
 
+$result = $a |> fn1(...) || $b |> fn2(...);
+
+$result = $value |> fn1($inner |> transform(...)) |> fn2(...);
+
+$result = $veryLongValue |> someFunction($innerValue |> innerTransform(...) |> anotherInnerTransform(...) |> yetAnotherInnerTransform(...)) |> finalTransform(...);
+
 =====================================output=====================================
 <?php
 
 $result = "Hello, World!" |> strtoupper(...);
-$result = "Hello, World!" |> (strtoupper(...) |> trim(...));
-$result =
-    "Hello, World!" |>
-    (strtoupper(...) |> (trim(...) |> htmlspecialchars(...)));
+$result = "Hello, World!" |> strtoupper(...) |> trim(...);
+$result = "Hello, World!"
+    |> strtoupper(...)
+    |> trim(...)
+    |> htmlspecialchars(...)
+;
 
 return $value |> transform(...);
 echo $value |> format(...);
@@ -45,8 +53,24 @@ $result = $value ?? ($fallback |> fn1(...));
 
 foo($value |> transform(...), $other);
 
-$veryLongVariableName |>
-    (someVeryLongFunctionName(...) |> anotherVeryLongFunctionName(...));
+$veryLongVariableName
+    |> someVeryLongFunctionName(...)
+    |> anotherVeryLongFunctionName(...)
+;
+
+$result = $a |> fn1(...) || ($b |> fn2(...));
+
+$result = $value |> fn1($inner |> transform(...)) |> fn2(...);
+
+$result = $veryLongValue
+    |> someFunction(
+        $innerValue
+            |> innerTransform(...)
+            |> anotherInnerTransform(...)
+            |> yetAnotherInnerTransform(...),
+    )
+    |> finalTransform(...)
+;
 
 ================================================================================
 `;

tests/pipe/pipe.php

@@ -15,3 +15,9 @@
 foo($value |> transform(...), $other);
 
 $veryLongVariableName |> someVeryLongFunctionName(...) |> anotherVeryLongFunctionName(...);
+
+$result = $a |> fn1(...) || $b |> fn2(...);
+
+$result = $value |> fn1($inner |> transform(...)) |> fn2(...);
+
+$result = $veryLongValue |> someFunction($innerValue |> innerTransform(...) |> anotherInnerTransform(...) |> yetAnotherInnerTransform(...)) |> finalTransform(...);